Answer:
It is C
Step-by-step explanation:
Here are the sentences with a:
Fabian has a brother.
Marisol obeys rules.
Tell the manager.
I have friends.
Samuel looks at Pedro.
If you take out the a:
Fabian has a brother.
Marisol obeys rules.
Tell him manager.
I have friends.
Samuel looks at Pedro.
As you can see, only one of them doesnt make sense and needs a